ErditeNaFeS2 · 2H2O

Erdite is extremely rare at MSH.

PHYSICAL CHARACTERISTICS:

Color is usually dark copper-red to bronze.Luster is metallic.Diaphaneity is translucent to opaque. Crystal System is monoclinic; C2/c.Crystal Habits include flattened, twisted and curled wire-like crystals.Cleavage {110} is good.Fracture is ??.Hardness is 2.Specific Gravity is approximately 2.3 g/cm3.Streak is black.Associated Minerals include lovozerite, natrolite, rasvumite, sidorenkite, sodalite, tugtupite, ussingite and vuonnemite.Distinguishing Features: Crystal habits.Origin: Named in 1980 after Richard C. Erd (b.1924), U.S. mineralogist who first synthesized the compound.